Objectives: Presbyacusis, one of the most common ailments of the elderly, is often treated with hearing aids, which serve to reintroduce some or all of those sounds lost to peripheral hearing loss. However, little is known about the underlying changes to the ear and brain as a result of such experience with sound late in life. The present study attempts to model this process by rearing aged CBA mice in an augmented acoustic environment (AAE).
Design: Aged (22-23 months) male (n = 12) and female (n = 9) CBA/CaJ mice were reared in either 6 weeks of low-level (70 dB SPL) broadband noise stimulation (AAE) or normal vivarium conditions. Changes as a function of the treatment were measured for behavior, auditory brainstem response thresholds, hair cell cochleograms, and gamma aminobutyric acid neurochemistry in the key central auditory structures of the inferior colliculus and primary auditory cortex.
Results: The AAE-exposed group was associated with sex-specific changes in cochlear pathology, auditory brainstem response thresholds, and gamma aminobutyric acid neurochemistry. Males exhibited significantly better thresholds and reduced hair cell loss (relative to controls) whereas females exhibited the opposite effect. AAE was associated with increased glutamic acid decarboxylase (GAD67) levels in the inferior colliculus of both male and female mice. However, in primary auditory cortex AAE exposure was associated with increased GAD67 labeling in females and decreased GAD67 in males.
Conclusions: These findings suggest that exposing aged mice to a low-level AAE alters both peripheral and central properties of the auditory system and these changes partially interact with sex or the degree of hearing loss before AAE. Although direct application of these findings to hearing aid use or auditory training in aged humans would be premature, the results do begin to provide direct evidence for the underlying changes that might be occurring as a result of hearing aid use late in life. These results suggest the aged brain retains significantly anatomical, electrophysiological, and neurochemical plasticity.
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http://dx.doi.org/10.1097/AUD.0b013e318269ca5b | DOI Listing |
Braz J Otorhinolaryngol
January 2025
Shanghai Jiao Tong University, School of Medicine, Hainan Branch of Shanghai Children's Medical Center, Department of Otorhinolaryngology, Sanya, China; Shanghai Jiao Tong University, School of Medicine, Shanghai Children's Medical Center, Department of Otorhinolaryngology, Shanghai, China. Electronic address:
Objective: We aimed to investigate the correlation between prevalent risk factors for high-risk neonates in neonatal intensive care unit and their hearing loss, and to examine the audiological features and genetic profiles associated with different deafness mutations in our tertiary referral center. This research seeks to deepen our understanding of the etiology behind congenital hearing loss.
Methods: We conducted initial hearing screenings, including automated auditory brainstem response, distortion product otoacoustic emission, and acoustic immittance on 443 high-risk neonates within 7 days after birth and 42 days (if necessary) after birth.
Braz J Otorhinolaryngol
January 2025
Ankara Yıldırım Beyazıt University Faculty of Medicine, Department of Otorhinolaryngology, Ankara, Turkey.
Objectives: The aim of this study was to investigate the risk factors that may cause postoperative otomycosis in patients undergoing Chronic Nonsuppurative Otitis Media (CNSOM) surgery.
Methods: In this retrospective study, 409 out of 523 patients met the inclusion criteria. 44 patients diagnosed with otomycosis CNSOM were analyzed.
Lang Speech
January 2025
Department of Educational Psychology, Leadership, & Counseling, Texas Tech University, USA.
Adapting one's speaking style is particularly crucial as children start interacting with diverse conversational partners in various communication contexts. The study investigated the capacity of preschool children aged 3-5 years ( = 28) to modify their speaking styles in response to background noise, referred to as noise-adapted speech, and when talking to an interlocutor who pretended to have hearing loss, referred to as clear speech. We examined how two modified speaking styles differed across the age range.
View Article and Find Full Text PDFAnn Otol Rhinol Laryngol
January 2025
Department of Otolaryngology-Head and Neck Surgery, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.
Objectives: The primary objective of this case series is to assess the effectiveness of the off-label use of the PROPEL drug-eluting stent, traditionally FDA-approved for sinus surgery, in preventing restenosis following canalplasty in patients with chronic otologic conditions or congenital anomalies. The stent provides both mechanical support to maintain canal patency and localized steroid delivery to reduce inflammation and scarring.
Methods: Four patients with various otologic conditions underwent canalplasty, followed by the placement of drug-eluting stents into the external auditory canal.
J Morphol
January 2025
Department of Zoology, Denver Museum of Nature & Science, Denver, Colorado, USA.
The barn owl is a common research subject in auditory science due to its exceptional capacity for high frequency hearing and superb sound source localization capabilities. Despite longstanding interest in the auditory performance of barn owls, the function of its middle ear has attracted remarkably little attention. Here, we report the middle ear transfer function measured by laser Doppler vibrometry and direct measurements of inner ear pressures.
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